Numerous Volunteer units had been organised across Britain at the time for home defenceof the French Revolutionary Wars, and some of these had taken on the role of manning coast artillery guns.

The first headquarters (HQ) was an office in Broad Street, then a wooden building on the Kirk Green until that was replaced by a purpose-built drill hall on reclaimed land on the shore of the Peerie Sea.

[7][8][9][10][12][13] When the Volunteers were subsumed into the new Territorial Force (TF) under the Haldane Reforms of 1908,[15][16] the Orkney RGA transferred as a 'defended ports unit' with minor changes to organisation and uniforms.

Shearer raised two companies, which were designated the Orkney Coast Brigade, RGA when the TF was reorganised as the Territorial Army (TA) in 1921.

[18] In 1926 it was decided that the coastal defences of Great Britain should be solely manned by part-time soldiers of the TA.

[25][26] However, there were by now no TA units existing in Orkney or Shetland, and new ones had to be hastily raised after the Munich Crisis in 1938.

Other ranks had scarlet piping round the collar and Austrian knots above the cuffs, officers had them in silver.

The headgear was a blue peaked cap with a black band and scarlet piping, with the Royal Arms badge.